Physical vapor deposition (“PVD”) methods can used to form a film or layer of material on a substrate surface. PVD methods can be used in, for example, semiconductor fabrication processes to form metallized layers in the fabrication of integrated circuitry structures and devices. Sputter deposition is a PVD method in which a glow plasma discharge bombards a sputtering target which releases atoms that are subsequently deposited onto a substrate.
A diagrammatic view of a portion of an exemplary sputter deposition apparatus 8 is shown in FIG. 1. In one configuration, a sputtering target assembly 10 comprises a backing plate 12 having a target 14 bonded thereto. A substrate 18 such as a semiconductive material wafer is within the sputter deposition apparatus 8 and provided to be spaced from the target 14. As shown, the target 14 is disposed above the substrate 18 and is positioned such that a sputtering surface 16 faces substrate 18.
In operation, sputtered material 22 is displaced from the surface 16 of target 14 and forms a thin film 20 on substrate 18. In some embodiments, suitable substrates 18 include wafers used in semiconductor fabrication. For example, the target 14 is bombarded with energy until atoms from the surface 16 are released into the surrounding atmosphere and subsequently deposited on substrate 18. In some embodiments, plasma sputtering is used to deposit a thin metal film onto chips or wafers for use in electronics.
Problems can occur in the deposition process if particles are formed, as these particles may fall into or onto a deposited film and disrupt desired properties of the thin film. A sputter or particle trap can be included on a sputtering target to capture particles formed during a deposition process. Additionally, there remains a risk that captured particles may flake off of the sputtering target and disrupt the thin film. For example, loosely held particles may flake from a sputter trap during cyclic thermal stress. Accordingly, it is desired to develop a sputter or particle trap that can be applied to a sputtering component, such as a sputtering target, which captures and retains particles formed during a deposition process. Capture and retention of such particles reduces the probability that a particles falls onto the deposited film during the deposition process.